AP Chemistry Spectrometry

When a sample of an unknown element is injected into a mass spectrometer, these results are obtained. Estimate the average atomic mass of this element.

• 117 amu

• between 117 and 118 amu

• between 118 and 119 amu

• between 119 and 120 amu

Tags

NGSS.HS-PS1-7

The average atomic mass of a chlorine atom is 35.45 amu. Chlorine consists of two isotopes, ³⁵Cl and ³⁷Cl. Which of the following most closely approximates the relative abundance of these isotopes?

• 25% ³⁵Cl and 75% ³⁷Cl

• 50% ³⁵Cl and 50% ³⁷Cl

• 75% ³⁵Cl and 25% ³⁷Cl

• 90% ³⁵Cl and 10% ³⁷Cl

Tags

NGSS.HS-PS1-8

Substance AB₂ is 60.0% A by mass. What is the percent A by mass for substance AB?

• 20.0%

• 40.0%

• 60.0%

• 75.0%

What mass of aluminum is required if 40.0 g of iron (III) oxide, Fe₂O₃ (molar mass 159.7 g/mol), is to be completely consumed in the following reaction? Fe₂O₃ (s) + 2 Al (s) -> 2 Fe (l) + Al₂O₃ (s)

• 13.5 g

• 27.0 g

• 40.0 g

• 67.0 g

Tags

NGSS.HS-PS1-7

Identify the element whose photoelectron spectrum is shown here.

• O

• Ca

• Ti

• Ge

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2